Artificial leg



R. S. DAVIDSON ARTIFICIAL LEG Feb. 1, 1955 2 Sheets-Sheet 1 Filed Nov. 5, 1953 ATTORNEYS Feb. 1, 1955 R. s. DAVIDSON ARTIFICIAL LEG 2 Sheets-Sheet 2 Filed Nov. 5, 1953 INVENTOR. k g'iflanwsozz ATTE! RN EYS United States Patent ARTIFICIAL LEG Ruby S. Davidson, Covington, Tenn., assignor of one-half to Jessie M. Sanders, Covington, Tenn.

Application November 5, 1953, Serial No. 390,315

2 Claims. (Cl. 3-24) This invention relates to an artificial leg, and more particularly to a locking joint for an artificial leg.

The object of the invention is to provide an artificial leg which will automatically lock itself in the proper adjusted position.

Another object of the invention is to provide an artificial leg which can be readily locked in any desired angular position, there being a hinge joint interconnecting the upper and lower sections of the leg together.

A further object of the invention is to provide an artificial leg which is extremely simple and inexpensive to manufacture.

Other objects and advantages will be apparent during the course of the following description.

In the accompanying drawings, forming a part of this application, and in which like numerals are used to designate like parts throughout the same:

Figure l is a side elevational view showing the artificial leg with the joint of the present invention.

Figure 2 is a view taken at right angles to the view shown in Figure 1.

Figure 3 is a fragmentary elevational view, with parts broken away and in section showing the joint for the leg.

Figure 4 is a vertical sectional view taken through the joint of Figure 3 and showing the tongue locked or maintained outwardly by the spring member.

Figure 5 is a view similar to Figure 4 but showing the tongue held inwardly by the spring member.

Figure 6 is a perspective view showing the various parts of the joint for the artificial leg.

Referring in detail to the drawings, the numeral 10 designates an artificial leg which may be made of any suitable material such as metal, and the artificial leg 10 includes an upper section 11 and a lower section 12. Hingedly connecting the upper section 11 and lower section 12 together, is a pair of hinge joints 14 and it will be seen from Figure 2 of the drawings that a pair of the hinge joints 14 are provided for each of the legs.

Each hinge joint 14 has the same construction and each includes a body member 15 which is arranged contiguous to the inner surface of the top section 11. The body member 15 includes an inner arm 16, and arranged contiguous to each side of the arm 16 is a side wall 20, Figure 6. The arm 16 is provided with a cutout 17 which defines a shoulder for a purpose to be later described. The side walls and the inner arm 16 are provided with registering openings 18, and extending through the registering openings 18 and through the top section 11 of the leg are suitable bolt and nut assemblies 19 which serve to secure the body member 15 to the top section 11. The lower portion of the arm 16 is provided with a plurality of teeth 21 for a purpose to be later described.

It will be seen from Figure 6 of the drawings that the lower ends of the side walls 20 are spaced apart to define a space 22, and the side walls 20 are each provided with registering slots 23. A support member 24 is arranged contiguous to the inner surface of the bottom section 12, and the support member 24 is provided with a plurality of apertures 25. Suitable securing elements such as bolt and nut assemblies 26 extend through the apertures and through the bottom section 12 for securing the support member 24 to the bottom section.

A pivot pin 27 extends through the support member 24 and through the registering slots 23, the upper portion of the support member 24 being pivotally mounted in the space 22 between the side walls 20. There is further provided on the upper end of the support member 24 a plurality of teeth 28 which are mounted for movement into and out of engagement with the teeth 21 on the arm 16. A finger 29 extends from the upper end of the support member 24, and the finger 29 is adapted to coact with the shoulder formed by the cutout 17 so as to limit pivotal movement of the parts.

The artificial leg of the present invention further includes a pivotally mounted tongue 32. The tongue 32 is pivotally mounted between a pair of apertured cars 30 by means of a pin 31, and the ears 30 can be secured to one of the side walls 20. A cutout 39 may be arranged in the top section 11 adjacent the joint, Figure 1, so as to provide sufiicient clearance for the projection therethrough of the ears 30. The tongue 32 is provided with a lug 33 which is mounted for movement into and out of engagement with the adjacent slot 23, as shown in Figures 4 and 5. The tongue 32 is further provided with a pair of notches 34 which are adapted to be engaged by a projection 36 on a spring member 37. The spring member 37 is provided with an aperture 38 through which projects the lowermost of the bolt and nut assemblies 19. A suitable opening 40 is provided in the tongue 32 for the passage therethrough of the pivot pin 31, Figure 6.

From the foregoing it will be apparent that the present invention includes a pair of hinge joints 14 for connecting each of the upper and lower sections together. The pin 27 passes through the registering slots 23 and the elongated slots 23 permit the parts to be arranged as shown in Figure 4 so that the lug 33 is out of engagement with the adjacent slot 23. Thus, the lower section 12 can pivot with respect to the upper section 11 when the parts are in the position shown in Figure 4. In Figure 5 the lug 33 is arranged in engagement with the adjacent slot 23 so that the lower section 12 will be locked in its adjusted position. A spring member 37 maintains the tongue 32 in the position shown in Figure 4 or in the position shown in Figure 5 but by applying a slight manual pressure on the tongue 32 it can be moved even though it is engaged by the spring member 37. The interengaging teeth 21 and 28 serve to hold the lower section 12 immobile in its various adjusted positions when the teeth are arranged in engagement with each other. However, the elongated slots 23 permit the teeth 28 on the support member 24 to be moved away from the teeth 21.

The hinges can be made in any desired size and can be made of any type of material such as metal or plastics. By maintaining the latch or tongue 32 in the position shown in Figure 4 the support member 24 and the lower section 12 will move downwardly slightly due to the slots 23 and then by pressing inwardly on the tongue 32 the lug 33 will move into the adjacent slot 23 so that the lower section 12 can be locked in any desired angular position. The artificial leg works itself by the motion of the stump.

In use when the upper part 11 of the leg is raised, the lower part 12 drops down and swings free and when the upper part 11 is pressed down the leg is locked at any angle desired. The leg works automatically and operates with the same motion as if it were a natural leg since when the upper part 11 is raised the Weight of the lower part 12 pulls downwardly and permits the lower part to swing free. Then, when the lower part 12 is pressed on it is locked and then the tongue 32 can be manually set or moved from the position shown in Figure 4 to the position shown in Figure 5 so that the lower part can be locked in any desired angular position.

I claim:

1. In an artificial leg, an upper section and a lower section, means hingedly connecting said sections together, said means comprising body members secured to the inner surface of said upper section, and a support member secured to the inner surface of said lower section for coaction with said body member, said body member including an arm, a pair of spaced parallel side walls arranged on opposite sides of said arm and secured thereto, interengaging means on said arm and support member, said interengaging means comprising teeth on said support member and arm, there being a cutout in said arm providing a stop shoulder, a finger extending from said support member for engagement with said shoulder, there being registering slots in said side walls, and a pin extending through said support member and through said registering slots, a pair of spaced parallel apertured ears extending from one of said side walls and secured thereto, a tongue pivotally mounted between said pair of cars and including a lug mounted for movement into and out of engagement with one of said lots, there being a plurality of notches arranged in said tongue, and a spring member arranged in engagement with said notches.

2. In an artificial leg, an upper section and a lower section, means hingedly connecting said sections together, said means comprising body members secured to said upper section, and a support member secured to said lower section for coaction with said body member, said body member including an arm, a pair of side walls arranged on opposite sides of said arm and secured thereto, interengaging means on said arm and support member, said interengaging means comprising teeth on said support member and arm, there being a cutout in said arm providing a stop shoulder, a finger extending from said support member for engagement with said shoulder, there being registering slots in said side walls, a pin extending through said support member and through said registering slots, a pair of apertured ears extending from one of said side walls and secured thereto, a tongue pivotally mounted between said pair of ears and including a lug mounted for movement into and out of engagement with one of said slots, there being a plurality of notches arranged in said tongue, and resilient means arranged in engagement with said notches.

References Cited in the file of this patent UNITED STATES PATENTS 2,327,042 Hinkle Aug. 17, 1943 2,591,373 Petruch Apr. 1, 1952 FOREIGN PATENTS 462,302 Italy Mar. 9, 1951 

